When I'm braking from speed, like when coming off a motorway onto a slip, I get a lot of vibration in the car and the steering wheel. It does do it when when braking at slower speeds as well but is not as noticeable.
If I slow to a crawl and brake I think I can feel it "pinching" periodically like a buckled wheel on a bicycle would do.

I read some posts on here and other forums suggesting pad deposits and warped discs. So I started by doing some brake cleansing by braking hard from high speed a few times as per a tutorial. This didn't fix it.

Since my OBC said my pads would need changing in a few thousand miles, I thought I'd replace all 4 pads and the discs on the front too. After doing this I followed a bedding in tutorial. This has also not helped the problem.

I have also changed the wheels (from winter to summer) which hasn't helped.

There is no wobbling etc whilst driving at any speed so I don't think it's a balance problem.

The hub to disc mating surface needs to be absolutely free of any rust or other contamination when replacing the discs. My guess is that the this is the source of the problem.

It could be warped discs if they are of poor quality or have been abused. I think that the only real answer is to check for run-out on each disc and either replace the discs on the axle concerned or, as a first pass, remove each discs and clean the mating surfaces until they are spotless.

How far are your discs and pads gone? Mine started doing exactly as you described about a week before I changed them all round and they were pretty much gone. Since the change all has been well.

Apologies but just a small

I'm interested in hearing more about the bushings as I have noticed mine starting to grab at camber changes and undulations but figure my geo may have gone out since changing the wheels. Something I'll be sorting once I get a new suspension setup.

A couple of thousand miles, if that. I just changed them. I thought that might be what the cause was originally which is partly why I replaced them.

Sounds like a different problem then. Definitely get your hub run out checked along with the bushes and report back as I may need to do my bushes by the sounds of things. Time to upgrade to M3 stuff me thinks

Turned out to be a temporary solution as the brake wobble came back..... swapped the discs AGAIN on the rear. Fixed...... came back a few months later. Had the discs machined on the car with a Procut lathe. Fixed. Now a few months on, it's back again!

I bought a dial gauge and it's the O/S rear that has the most runout, but only about 0.08mm compared to 0.02 on the N/S. I checked this before I had them machined.

There was no runout on the hubs that I could detect.

I stripped and wire-brushed the caliper to remove all the rust and greased all the moving parts last time I fitted new discs but could it be this??

The one positive I've had out of this, is from never changing brake parts before, I can now replace discs and pads in about 10 minutes per corner

Hi Mate, Just read through your thread, I've got exactly the same thing, had my breaks changed all round twice. Apparently its because the car sits for long periods of time. What Bull****, i didnt spend all that money so that it messes up. I completely agree with the wanting to sell it part. Might don a break upgrade and see how it goes from there....

Out of interest, you arent greasing up the mating surfaces on the back of the discs are you? I know copper slipping the backs of the discs where it mates the hub is known for causing wheel wobble/brake judder issues...

Out of interest, you arent greasing up the mating surfaces on the back of the discs are you? I know copper slipping the backs of the discs where it mates the hub is known for causing wheel wobble/brake judder issues...

As I've done it many times now I've done one set of discs with nothing, then another set with some engine oil on the hub (recommended by a mechanic friend to stop it rusting so quick) and it made no difference to the wobble either way. Thanks for the suggestion though - all very welcome!

I had a similar problem years ago on a new car after its first service. The problem was front wheel judder when braking. Different front pads were fitted and front discs were checked. Did not help. Softer front pads made no difference either. I traced the fault myself to oval rear brake drums caused by overadjusted handbrake at the first service. The excess heat caused by the rubbing shoe had distorted the drums. The shape of the drums then sent hydraulic pulses to the front brakes which were the more efficient disc brakes making everybody believe it was a front brake problem. I wonder if the same thing is happening here, ie a fault on the rear discs is being transmitted to the more efficient front brakes along the hydraulic lines.